Why is this source code not working?

I'm trying to load txt file using constructor and save it at the end using destructor

---------------------------------------------

#include

#include

using namespace std;

class test

{

public:

test();

~test();

};

test::test()

{

ofstream myfile;

myfile.open("test.txt");

}

test::~test()

{

myfile.close();

}

int main()

{

test t;

myfile << "Is this working well?" << endl;

myfile << "Yes it is working well" << endl;

return 0;

}

-------------------------------------

// error note

test.cpp: In destructor test::~test():

test.cpp:21:1: error: myfile was not declared in this scope

myfile.close();

^~~~~~

test.cpp:21:1: note: suggested alternative: tmpfile

myfile.close();

^~~~~~

tmpfile

test.cpp: In function int main():

test.cpp:27:1: error: myfile was not declared in this scope

myfile << "Is this working well?" << endl;

^~~~~~

test.cpp:27:1: note: suggested alternative: tmpfile

myfile << "Is this working well?" << endl;

^~~~~~

tmpfile